Royal purple in auto trans

Discussion in '2015+ S550 Mustang 5.0L Tech' started by gary2014, Feb 6, 2018.

  1. gary2014

    gary2014 Junior Member

    i was wondering if any body used some Royal Purple Auto trans fluid in their S197 Auto Transmission
  2. Greg Hazlett

    Greg Hazlett Stepping on the Pink Bus

    What year car do you have? I use and sell Amsoil, everyone has their opinions on fluids but I have seen a lot of studies and video's of how bad RP is...if you are interested in using Amsoil and want a quote let me know.
  3. 86GT351

    86GT351 forum member

    Any Mods to the car? For a bone stock car it is not really needed in my opinion
  4. gary2014

    gary2014 Junior Member

    no it has a stage 2 Roush supercharger,373 rear ,kooks, and is dyno tuned
  5. gary2014

    gary2014 Junior Member

    IT'S A 2014 5.0
  6. Greg Hazlett

    Greg Hazlett Stepping on the Pink Bus

    Do you have an aftermarket TC?
  7. RocketcarX

    RocketcarX 95% of my weight is fuel

    I think the reason that RP engine oil is dyed purple is so you can't tell it's trash.

    I wouldn't pay money for anything they make, much less the $$$ they sell that stuff for.
  8. Pentalab

    Pentalab forum member

    I use Royal Purple 'Max ATF' in my 2010 auto... which is the 5r55s used in the 05-10 cars.
    Works superb, 100% synthetic, shifts are smooth. But I also installed a B+M auto tranny cooler.. model 70268.

    . Previously, my ATF temp would rise from 170 deg F, to 200 deg F in just 4-8 secs with the small Roush M90 blower on. After the auto tranny cooler installed, temps rise only 1-2 deg F with blower on. New tranny cooler is plumbed in series with oem cooler..and mounted directly below oem cooler. New cooler has a unique T stat, that operates on viscosity.

    I also installed the Performance automatic deeper aluminum auto tranny pan. Comes with a locking style dipstick, that comes up on the firewall on the pass side, next to battery. Dipstick opening is plenty big enough to easily add ATF fluid. New pan also comes with a drain plug..and also new bolts. I would suggest buying a new ford auto tranny gasket for any new tranny pan. The deeper version for the 11-14 cars that use the 6R80E auto tranny is
    here at
    It comes with 21 new SS pan bolts, and the pan holds an extra 3 qts.

    To get all the old ATF out, it was sucked out, right at the tranny cooler, with suction on one side, and some light pressure on the other side. I know several other folks who use RP max ATF in their 11-14 cars, and it runs a lot better than the oem atf. What ever brand atf you end up buying, make sure it's 100% synthetic.

    On a side not re: eng oil, I switched from oem ford motocraft 5W-20 semi synthetic (which is only 2-5% synthetic + 95-98% dino oil) to Royal Purple 5W-30 HPS. Previously, my eng catch can would end up 80% full, of what appeared to resemble a 'chocolate milk shake'..which is just unburnt fuel, oil and condensation / moisture). After the switch, the catch can barely catches anything, maybe 10-20% at most, and it pours out like new RP eng oil, no more choc shake.... go figure. Several other folks have gotten identical results to mine. A local buddy gets the RP products for me at his cost, so I just buy it in bulk, like 24 qts at a time.
    Last edited: Feb 7, 2018
  9. Lime1Gt

    Lime1Gt Junior Member

    Not really a fair comparison; You might get the same catch can results using Ford's Full Synthetic instead of Ford Syn-Blend as well.

    On transmission fluids I would use what ever meets the Ford spec for that particular trans as they each use different friction modifiers. Read your owners manual

    From owners manual "Automatic transmissions that require MERCON LV should only use MERCON LV fluid. See
    Scheduled Maintenance Information
    to determine the correct service interval. Use of any fluid
    other than the recommended fluid may cause transmission damage."


    From RP website. "Please Note:
    Max ATF is NOT recommended for the following applications: Allison TES-389, DEXRON® VI, Ford Type F and MERCON® SP & LV, Honda DW-1, Hyundai SP-IV and NWS-9638, Kia SP-IV, JWS 3324, MAN 339 Z3, Mercedes Benz 236.8, 236.12, 236.14 & 236.15, Mitsubishi SP-IV and ATF J2, Nissan Matic-S, Saab 93-165-147, Shell M-1375.4 (ZF 6-Speed AT), Toyota WS (JWS 3324) and ZF TE-ML 14C. Max ATF is not recommended for use in any CVT or DCT applications."
    Last edited: Feb 17, 2018
  10. Pentalab

    Pentalab forum member


    I should have mentioned that other folks had similar results to mine, when using other brands of 100% synthetic eng oil. No more choc shake in the catch can. The conclusion we all had was there is something amiss or substandard when using Ford motorcraft semi synthetic eng oil, or any other brand of semi synthetic eng oil. 100% dino oil is even worse, bottom of the barrel.

    The 5R55S auto tranny used in the 05-10 cars uses Mercon V for ATF. RP's... 'max ATF' is fully compatible with any auto tranny that uses Mercon V.

    Ford motorcraft Mercon V also has an identical disclaimer to the RP max ATF you posted above.

    Application. Motorcraft Mercon V® Transmission Fluid is recommended for all automatic transmissions requiring Ford Mercon V® transmission fluid. Five (5) quarts are required for a regular transmission maintenance flush.Technical Note. Do not use in applications where MERCON® SP, MERCON® LV, Continuously Variable Chain Type Transmission Fluid, Motorcraft® Premium Automatic Transmission Fluid, FNR5 Automatic Transmission Fluid or Type F Automatic Transmission Fluid is recommended. Fitment: 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018
    Ford motorcraft Mercon V is not 100% synthetic. It's only got a tiny bit of synthetic in it.

    RP's... 'MAX ATF' can be used in any mustang, from any least back to 1979.
    Will it fit my Mustang? Below is from AM's site..which is incorrect.
    • Bullitt - 01, 08, 09
    • EcoBoost - 15, 16, 17, 18
    • GT - 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 00, 01, 02, 03, 04, 05, 06, 07, 08, 09, 10, 11, 12, 13, 14, 15, 16, 17, 18
    • LX - 87, 88, 89, 90, 91, 92, 93
    • Mach 1 - 03, 04
    • Other - 79, 80, 81, 82, 83, 84, 85, 86
    • V6 - 94, 95, 96, 97, 98, 99, 00, 01, 02, 03, 04, 05, 06, 07, 08, 09, 10, 11, 12, 13, 14, 15, 16, 17
    ## The 6R80 uses mercon type LV (low viscosity) which is not compatible with RP's max ATF, nor Ford motorcraft mercon V, also sold by AM.

    ## The new 10R80 10 speed tranny uses mercon type ULV (ultra low viscosity), so again RP's max atf is not compatible.

    ## The OP has a 2014 auto with the 6R80, so RP's max atf is a no go. Since he has a Roush stage 2 blower setup, what he could do to lower temps a bit, and provide for a dipstick and greater capacity is to use a 2nd tranny cooler, and a PA deeper pan, holds an extra 3 qts. Then use ford motorcraft mercon LV.
    Last edited: Feb 18, 2018